基于铋纳米颗粒的自由沉降法制作X射线吸收光栅  

Fabrication of X-ray Absorption Gratings by Free Settling of Bismuth Nanoparticles

作　　者：雷耀虎[1] 许桂雯[1] 李乔飞 WALI Faiz 刘鑫[1] 李冀[1] 黄建衡[1] LEI Yao-hu;XU Gui-wen;LI Qiao-fei;WALI Faiz;LIU Xin;LI Ji;HUANG Jian-heng(Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province,College of Physics and Optoelectronic Engineering,Shenzhen University,Shenzhen,Guangdong 518060,China)

机构地区：[1]深圳大学物理与光电工程学院光电子器件与系统(教育部/广东省)重点实验室

出　　处：《光子学报》2019年第10期223-228,共6页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.61227802,61405120,61605119,61571305,11674232);深圳市自然科学基础研究(No.JCYJ20170302142617703);深圳大学教师启动项目(Nos.2017017,2018041)~~

摘　　要：利用深反应离子刻蚀技术或湿法腐蚀在硅上制作光栅结构,将与光栅浸润的液体作为载体携带铋纳米颗粒进入光栅结构内,形成致密排列,从而制作出X射线吸收光栅.致密地填充了周期为42μm、刻蚀深度为150μm的光栅结构,比较了其与微铸造法制作的铋块体吸收光栅的X射线吸收性能,并通过填充周期为24μm和6μm的光栅结构,研究了光栅周期与填充致密性之间的关系.扫描电镜测试结果显示自由沉降法可有效制作较大周期光栅,但对周期为6μm光栅结构填充的致密性不佳。分析结果表明,对于小周期吸收光栅,需筛选所用填充颗粒,以保证颗粒粒径远小于光栅槽宽.基于纳米颗粒的自由沉降法可降低光栅制作成本及技术门槛,方便实现大面积吸收光栅的制作.To fabricate X-ray absorption gratings,deep reactive ion etching and wet etching are used to fabricate grating structures on silicon wafers,and a liquid carrier,which is wet with the surface of grating structure,is used to bring the bismuth nanoparticles into grating structures in a dense arrangement.Then,a grating structure with the period of 42μm and depth of 150μm is filled.To show the performance of the fabricated absorption grating,a comparison with the bulk bismuth grating obtained by micro-casting method is provided.Moreover,the relationship between the grating period and the filling compactness through filling grating structures with periods of 24μm and 6μm is found.The scanning electron microscopy micrographs show the effectiveness of free settling method for the large-period grating structures.However,for the structures with 6μm period,the filling compactness is not satisfied.The results illustrate that bismuth nanoparticles that their diameters are much less than the width of grating structures should be selected for the small-period absorption gratings.Furthermore,nanoparticles-based free settling method lowers grating cost and technique threshold,and allows the fabrication of large-area absorption gratings.

关 键 词：X射线成像 吸收光栅 自由沉降 铋纳米颗粒 刻蚀 相位衬度 

分 类 号：TB559[理学—物理] O647.5[理学—声学]